Hilsenbergia leslieae J.S. Mill., 2003

Miller, James S., 2003, Classification of Boraginaceae subfam. Ehretioideae: Resurrection of the genus Hilsenbergia Tausch ex Meisn., Adansonia (3) 25 (2), pp. 151-189 : 174-177

9. Hilsenbergia leslieae J.S. Mill. , sp. nov.

Frutex vel arbor parva usque ad 5(-10) m alta, ramunculis glabris. Folia ad apice ramunculorum brachyblastorumve in fasciculos densos disposita; lamina obovata usque oblanceolata, 10-21(-30) mm longa, 6- 12(-16) mm lata, apice obtusa usque rotendata vel emarginata, basi cuneata , margine integra, leviter incrassata, utrinque glabra ; petiolo 2-5(-7) mm longo. Inflorescentiae terminale, cymosae. Flores bisexuales; calyce campanulato usque tubulari-campanulato, 4-4.5 mm longo, 5-lobo, extus glabro, intus apiceum versus dense pubescente; corolla alba , urceolata , 5-6 mm longa. Fructus drupaceus, ovoideus usque late-ovoideus, 4- 5.5 mm longus, 3-4 mm in diam.; pyrenis 4, porcati.

TYPUS. — Miller & Miller 3787, Madagascar, Prov. Toliara, 14 km SE of Tuléar on the road to Sakaraha, 100 m, 23°21’S, 43°42’E, fl., 26 Dec. 1988 (holo-, MO!; iso-, K!, MO!, P!) .

Shrub or small tree to 5(-10) m tall, thickstemmed, densely branched, the twigs glabrous, often glaucous and densely waxy with age. Leaves fasciculate at branch tips or on short lateral spur shoots, deciduous; blades obovate to oblanceolate, 10-21(-30) mm long, 6-12(-16) mm wide, (length:width ratio 3:1-3:2), the apex obtuse to rounded or emarginate, the base cuneate, the margin entire, slightly thickened, both surfaces glabrous, rarely minutely ciliate along the margin near the leaf base, the venation obscurely brochidodromous, the midrib even with the leaf surface, raised slightly below, the secondary veins 3-4, often indistinct, the tertiary venation reticulate; petioles 2-5(-7) mm long, less than half the length of the blade, or nearly sessile on young leaves, glabrous or rarely minutely puberulent, prominently canaliculate on the adaxial surface.

Inflorescences terminal, reduced cymes of 1- 3(-4) flowers, the branches glabrous. Flowers bisexual, on pedicel-like inflorescence branches 2-6 mm long; calyx campanulate to tubular-campanulate, 4-4.5 mm long, 3-4 mm wide, 5-lobed, the lobes valvate, triangular, 1-1.5 mm long, densely pubescent on the apical part of the interior surface, the outer surface glabrous; corolla white, urceolate, 5-6 mm long, 3-4 mm wide, 5-lobed, the lobes erect to spreading, ovate, 1- 2 mm long; stamens 5, the filaments 3-4 mm long, the upper 1-2 mm free, glabrous, the anthers ellipsoid, 1-1.5 mm long; ovary conical, 1.2-1.5 mm long, 0.8-1 mm wide, the style 1.5- 2 mm long, the 2 stigmas capitate and terminal.

Fruits drupaceous, color at maturity unknown, borne in the persistent cup-shaped to spreading calyx, ovoid to broadly ovoid, 4- 5.5 mm long, 3-4 mm in diameter, the endocarp bony, separating into 4 pyrenes at maturity, c. 4 mm long, c. 2.5 mm wide, ridged on the exterior surface. — Fig 12 .

Hilsenbergia leslieae is variable in habit, usually being an erect shrub or small tree, sometimes reaching 10 m in height (e.g. Humbert 28919), but occasionally is low and prostrate (e.g. SF28553, from wind-swept areas near Cap Sainte-Marie). This species appears to be closely related to, and is easily confused with, H. croatii and the differences between them are discussed under that species.

Hilsenbergia leslieae is named in honor of my wife, Leslie MILLER, who accompanied me during field studies for this project, including the collection of the type specimen.

DISTRIBUTION. — Hilsenbergia leslieae occurs in southern Madagascar ( Fig. 11 ) on calcareous substrates.

VERNACULAR NAMES. — Taikoaky, Tsingena.

CONSERVATION STATUS. — Provisional IUCN Red List Category: Endangered (EN B2ab(i-iv)). Hilsenbergia leslieae occurs at scattered localities in southern Madagascar, but it is infrequently collected and its Extent of Occurrence is only 60 km 2. It is known to occur in the Réserve Naturelle Intégrale de Tsimanampetsotsa.

PARATYPES. — MADAGASCAR: Chauvet 190, Prov. Toliara, route Sarodrano , Tuléar , fl., fr., 23°28’S, 43°46’E, 13 Nov. 1961 ( P!, TEF!) ; Humbert 5403, Prov. Toliara, du lac Tsimanampetsotsa, au delta de la Linta, près d’Itampolo, 1-10 m, 25°02’S, 44°04’E, fl., 17-24 Aug. 1928 ( P!) ; Humbert 28919, Prov. Toliara, environs d’Antanimora, 20-25 km au SSE, bush xérophile sur terrains cristallins, 200-500 m, 24°49’S, 45°40’E, fl., 6-9 Feb. 1955 ( P!) ; Perrier de la Bâthie 4434, Prov. Toliara, dunes au nord de Tsimanampetsotsa, 24°03’S, 43°43’E, fl., fr., June 1910 ( P!) ; Phillipson 3042, Prov. Toliara, SE of Tuléar on Route Nationale 7, 15 km from town, near La Table, 75 m, 23°25’S, 43°47’E, fl., 28 Dec. 1988 ( P!) ; Phillipson, Labat & Du Puy 3450, Prov. Toliara, 38 km SW of Ampanihy , on road to Androka, calcareous plateau, 200 m, 24°50’S, 44°25’E, fr., 5 Feb. 1990 ( P!) ; Service Forestier: SF11723 (Capuron), Prov. Toliara, sur les pentes du massif de l’Angavo, à l’est d’Antanimora , 200-530 m, 24°49’S, 45°40’E, fl., 24-25 Jan. 1955 ( P!) ; Service Forestier: SF25252 , Prov. Toliara, Tsimandaha, Antanimora , Dist. Ambovombe , 330 m, 24°49’S, 45°40’E, ster., 28 Oct. 1964 ( P!) ; Service Forestier: SF 25255 , Prov. Toliara, Tsimandaha, Antanimora , Dist. Ambovombe , 330 m, 24°49’S, 45°40’E, ster., 28 Oct. 1964 ( MO!, P!) ; Service Forestier: SF28553 (Capuron), Prov. Toliara, Cap Sainte-Marie et environs Nord du Cap, 25°34’S, 45°09’E, fl., 17 Dec. 1968 ( P!) .

Figures

Fig. 12. — Hilsenbergia leslieae J.S. Mill.: A, flowering branch; B, whole flower; C, open corolla with androecium and gynoecium; D, lateral and frontal view of anther; E, whole fruit with persistent calyx; F, lateral view of pyrene. A-D, Miller & Miller 3787; E, F, Phillipson et al. 3450. Drawn by A. JOUY.

Fig. 11. — Distributions of Hilsenbergia species, mapped on the simplified bioclimate zones of Madagascar (after CORNET 1974; see SCHATZ 2000).